The interchangeable dies in question can be used for clinching or for riveting, in particular for punch riveting. The die feature can be, for example, an axial recess which is realized in the manner of a truncated cone, with or without an elevation in the centre, etc.
The joining tool can be a tool which is suitable for the abovementioned joining process and comprises in particular a C-frame, on the one leg of which the tool, such as for example a punching tool, is arranged, and on the other leg of which the interchangeable die is secured.
A hitherto usual concept for fastening the interchangeable die on the die receptacle consists in providing a transverse bore toward the shank receptacle in the die receiving portion. The interchangeable die can be secured by means of said transverse bore, for example using a grub screw. This type of fastening, however, allows for an automated change of die only at great expense. In addition, the transverse bore is comparatively large such that as regards strength the die receiving portion is weakened.
To avoid the last-mentioned problem, it is known from document DE 20 2006 013 082 U1 to provide a die receiving portion with a bore, fastening means which are supported on the bore wall of the die receiving portion being provided in the bore in order to fasten a tool or a tool holder releasably on the die receiving portion. This can be effected, for example, as a result of a threaded engagement or as a result of a screw which cooperates with a tool holder by means of the bore, but from an end which is opposite the die. For axial securement, the document also describes providing clamping means which can be realized according to the end face wedge principle or are realized using elastomer elements.
Although the problem of having to provide a transverse bore in the die receiving portion for securing the die is avoided in this way, an automatic die change can still only be realized with difficulty.
Interchangeable dies which can be exchanged comparatively simply are known, for example, from document DE 103 35 085 A1. The interchangeable dies shown here comprise a die head and a die shank, a radial groove being realized on the die shank. Quick change receiving means, which can be realized, for example, as latching, tightening or clamping connections, can be provided on a C-frame. In addition, the document discloses a changing station in which tool-heads and dies can be held in storage.